Hot Water vs. Cold Water
By John Cowens

To view John Cowens article on Wondrous Water click here.

Materials:

• glass tumbler


• small pan


• small electric hot plate


• spoon


• water


• cane sugar

Procedure:

1. Fill the tumbler half full of cold water.
2. Add sugar, a teaspoonful at a time, and stir.
3. Continue to add sugar to the water until no more will dissolve. The solution will then become a saturated solution.
4. Pour it into the small pan and heat very gently on the hot plate.
5. When the solution is hot, add more sugar. You will find that much more sugar will dissolve now.

Try this experiment using salt in place of sugar. Heating the water will not increase the amount of salt it can dissolve.

Experimenting with other solvents
The need for solvents other than water is demonstrated in the following experiment.

Materials:

• hot water


• cold water


• teaspoon


• butter


• glass tumbler


• small bottle with stopper


• denatured alcohol or alcohol used in a car's radiator (rubbing alcohol will not work since it is diluted with water)


• mayonnaise or jelly jar


• sealing wax

Procedure:

1. Crush a piece of sealing wax until you have enough small fragments to fill a teaspoon.
2. Place them in a tumbler of cold water and stir the mixture. You'll notice that cold water will not soften or dissolve sealing wax.
3. Remove the pieces of sealing wax and place them into a tumbler of boiling water. Now you'll notice that hot water will soften sealing wax slightly.
4. Remove the sealing wax from the tumbler and drain off the water.
5. Place the recovered wax in a small mayonnaise jar or jelly glass. Don't use a good tumbler unless you have plenty of alcohol to clean it. Otherwise you will need to throw it away after this experiment.
6. Pour enough alcohol into the tumbler to cover the wax to a depth of about 2.5 centimeters.
7. Place a cover over the tumbler to prevent the alcohol from evaporating. Let it sit for an hour undisturbed. After one hour you'll notice the alcohol has become discolored and most of the sealing wax has softened and dissolved.



8. When the sealing wax has dissolved, add enough water to half fill the tumbler. The alcohol will be so diluted that it will leave the solution and form a thick gum. This substance may be used for finishing woodwork and is dissolved in alcohol.

Alcohol has many uses as a solvent in industry, the arts and medicine. Alcoholic solutions of drugs are called tinctures. A familiar tincture is called "Tincture of Iodine." It is a solution of iodine in alcohol. Even the perfume industry makes use of alcohol to dissolve essentials oils that supply perfumes with their fragrance. No substitute for this purpose is known. Finally, certain flavoring extracts, such as vanilla, require alcohol as a solvent. Does anyone know why vanilla extract makes such a great cologne for men?

To view John Cowens article on Wondrous Water click here.

John Cowens teaches sixth grade at Fleming Middle School in Grants Pass, OR.

January, 2007 Volume 37, Number 4